When remote WebDriver is being destroyed and the reusable session should be stored, then the browser is not closed.
https://github.com/arquillian/arquillian-extension-drone/blob/master/drone-webdriver/src/main/java/org/jboss/arquillian/drone/webdriver/factory/RemoteWebDriverFactory.java#L183-L187

Steps to reproduce: run ReusableRemoteWebDriverTestCase with visible browser (eg. firefox)